Megakaryocytopoiesis is the cellular development process that leads to platelet production. THPO is a humoral growth factor that is necessary for megakaryocyte proliferation and maturation, as well as for thrombopoiesis. THPO is the ligand for MLP/C_MPL, the product of myeloproliferative leukemia virus oncogene.Megakaryocytopoiesis is the cellular development process that leads to platelet production. The protein encoded by this gene is a humoral growth factor that is necessary for megakaryocyte proliferation and maturation, as well as for thrombopoiesis. This protein is the ligand for MLP/C_MPL, the product of myeloproliferative leukemia virus oncogene.